RFID sensors are commonly used in various applications, including object tracking and providing unique identification. Typical applications include identification badges, toll collection and payment systems, building access control, and inventory and asset control. RFID sensors can be either active or passive. An active RFID system utilizes an onboard battery to transmit signals from the sensor to a reader according to a pre-determined rate or interval. Passive RFID sensors utilize the energy transmitted by an antenna on the reader to generate and signal a response from the sensor back to the reader as desired or requested. RFID technology can also be utilized in conjunction with a number of different sensors to measure and transmit data of various types such as, for example, temperature, pressure, and strain.
Side-flexing metal conveyor belts have been used in spiral conveyor applications for many years. In spiral conveyor applications, the belt is wrapped around a central rotating drum in a helical path to permit a long path within the confines of a relatively small overall footprint. The inherent strength, durability, and open but adequate product support area of these types of belts generally makes them a good option for spiral process conveyors.
For the belt to operate with a reduced tension, it is typically preferred that the rotational speed of the central drum exceed the linear speed of the belt. The difference in travel distances between the belt and the outer surface of the drum per one complete revolution of the belt is known as overdrive. Overdrive can be an important indicator of the proper setup of a spiral conveyor system. Changes in the value of the overdrive can alter the belt tension, which in turn can affect overall belt service life. Conventionally, the only reliable way to determine the overdrive of the spiral cage has been to manually measure the travel differential between the belt and the drum. In addition, overdrive on spiral conveyors with a belt that is moving quickly can be difficult if not impossible to accurately measure.
Therefore, there is a need for a system that more easily provides measurements for determining the overdrive of a spiral conveyor.